KR20160016923A - Optical film, polarizer, image display device, and optical-film manufacturing device - Google Patents

Abstract

Disclosure of the Invention An object of the present invention is to provide an optical film free of wrinkles and excellent in adhesion between a support and an alignment film, and a polarizing plate and an image display device using the optical film. The optical film of the present invention is an optical film having a transparent support, an orientation film, and an optically anisotropic layer in this order, wherein the transparent support comprises an acrylic resin, a thickness between 50 nm and 200 nm, The optical film has a mixed layer in which the constituent material of the transparent support and the constituent material of the orientation film are mixed.

Description

TECHNICAL FIELD [0001] The present invention relates to an optical film, a polarizing plate, an image display device, and a method of manufacturing an optical film.

The present invention relates to an optical film, a polarizing plate, an image display apparatus, and a method for producing an optical film.

BACKGROUND OF THE INVENTION [0002] A retardation film made of an optically anisotropic material is used in display devices such as an LCD display device, an organic EL display device, a touch panel, and a luminance enhancement film.

As such a retardation plate, a cellulose-based resin film (particularly, a cellulose acylate (TAC) film) is generally used as a support (for example, see Patent Documents 1 and 2).

Here, it is known that a cellulose acylate (TAC) film has a large dimensional change with respect to temperature and humidity (see, for example, Patent Document 3), and the orientation film expands and contracts according to the dimensional change of the support, There is a problem that the retardation changes in the plane (particularly, at the end).

Patent Document 1: JP-A-2008-217001 Patent Document 2: JP-A-2012-008170 Patent Document 3: JP-A-2011-191756

The inventors of the present invention have made studies on an acrylic resin having a small dimensional change with respect to humidity or temperature as a material of a support. As a result, depending on the solvent used in the coating liquid forming the alignment film provided on the support, Or the adhesion between the support and the alignment film may be poor.

Accordingly, it is an object of the present invention to provide an optical film free of wrinkles and excellent in adhesion between a support and an orientation film, and a polarizing plate and an image display device using the optical film.

The inventor of the present invention has conducted intensive studies to attain the above object. As a result, the present inventors have found that, by forming a mixed layer of a specific thickness in which the constituent materials of the transparent support and the constituent materials of the orientation film are mixed between the support and the orientation film, The present invention has been completed based on this finding.

That is, it has been found that the above object can be achieved by the following constitution.

[1] An optical film having a transparent support, an orientation film, and an optically anisotropic layer in this order,

Wherein the transparent support comprises an acrylic resin,

An optical film having a thickness of 50 nm to 200 nm and a mixed layer in which constituent materials of a transparent support and constituent materials of an orientation film are mixed between a transparent support and an orientation film.

[2] An optical film according to [1], wherein the in-plane retardation at an optical anisotropic layer at a wavelength of 550 nm is 40 nm to 240 nm.

[3] The optical film according to [1] or [2], wherein the orientation film comprises a polyvinyl alcohol derivative.

[4] The optically anisotropic layer according to any one of [1] to [3], wherein the optically anisotropic layer is a patterned optically anisotropic layer having at least two retardation regions different in at least one of an in-plane slow axis direction and an in- plane retardation. Optical film.

[5] The optical film according to any one of [1] to [4], further comprising a hard coat layer.

[6] An optical film according to any one of [1] to [5], and a polarizer having a polarizer.

[7] An image display apparatus comprising an optical film according to any one of [1] to [5], a polarizer, and a liquid crystal cell or an organic EL display panel.

[8] An image display device according to [7], wherein an optical film, a polarizer, and a liquid crystal cell are provided in this order from the viewer side.

[9] An image display device according to [7], wherein a viewer, a polarizer, an optical film, and a liquid crystal cell are provided in this order from the viewing side.

[10] An image display device according to [7], wherein a viewer, an optical film, and an organic EL display panel are provided in this order from the viewer side.

[11] A process for producing an optical film according to any one of [1] to [5]

An alignment film is formed on a transparent support containing an acrylic resin by using a coating solution containing one or more solvents and having an average SP value of the solvent of 25 to 55. The alignment film is formed between the transparent support and the alignment film A mixed layer / orientation film forming step of forming a mixed layer having a thickness of 50 nm to 200 nm and containing a constituent material of the transparent support and a constituent material of the orientation film,

An optically anisotropic layer forming step of forming an optically anisotropic layer on the alignment film by using a composition for forming an optically anisotropic layer containing a liquid crystalline compound to produce an optical film.

[12] The process for producing an optical film according to [11], wherein the solvent has an average SP value of 25 to 40.

[13] The method for producing an optical film according to [11] or [12], wherein the solid concentration of the coating liquid is 60 mass% or less.

According to the present invention, it is possible to provide an optical film free of wrinkles and excellent in adhesion between the support and the orientation film, and a polarizing plate and an image display device using the optical film.

1 (A) to 1 (C) are schematic sectional views showing an example of the optical film of the present invention.
2 (A) and 2 (B) are schematic sectional views showing an example of a polarizing plate of the present invention.
3 (A) to 3 (D) are schematic sectional views showing an example of an image display apparatus (liquid crystal display apparatus) of the present invention.
4A and 4B are schematic sectional views showing an example of an image display apparatus (organic EL display apparatus) of the present invention, respectively.
5 is a photograph of a cross section of a laminate comprising a transparent support, a mixed layer and an orientation film taken at a magnification of 50,000 times by a scanning electron microscope (SEM).
6A to 6C are schematic front views showing an example of the patterned optically anisotropic layer, respectively.
7 is a schematic diagram showing an example of a polarizing plate (pattern circular polarizing plate) of the present invention.

Hereinafter, the present invention will be described in detail.

Descriptions of the constituent elements described below may be made on the basis of exemplary embodiments of the present invention, but the present invention is not limited to such embodiments.

Also, in this specification, the numerical value range indicated by using "~ " means a range including numerical values described before and after" ~ "as a lower limit value and an upper limit value.

Next, terms used in this specification will be described.

[Reaction (Re)]

Re (?) And Rth (?) Represent retardation in the plane and retardation in the thickness direction at the wavelength?, Respectively. Re (?) Is measured by using KOBRA 21ADH or KOBRA WR (both manufactured by Oji Scientific Co., Ltd.) with light having a wavelength of? Nm incident in the film normal direction. In the selection of the measurement wavelength? Nm, the wavelength selection filter can be manually changed, or the measurement value can be converted into a program or the like and measured. Details of a method of measuring Re (?) And Rth (?) Are described in paragraphs 0010 to 0012 of Japanese Laid-Open Patent Publication No. 2013-041213, the contents of which are incorporated herein by reference.

In the present specification, when there is no particular addition to the measurement wavelength, the measurement wavelength is 550 nm.

In the present specification, an angle (for example, an angle such as "90 DEG") and its relation (for example, "orthogonal "," parallel ", " Are to be construed as including a range of allowable errors in the technical field to which the present invention belongs. In this case, the allowable error means, for example, that it is within a range of a strict angle of less than +/- 10 DEG, and specifically, the error with a strict angle is preferably not more than 5 DEG, more preferably not more than 3 DEG .

1. Optical film

The present invention relates to an optical film having a transparent support, an orientation film and an optically anisotropic layer in this order.

Here, the optical film of the present invention is an optical film having a mixed layer of a specific thickness in which a transparent support contains an acrylic resin and a constituent material of the transparent support and a constituent material of the orientation film are mixed between the transparent support and the orientation film .

As described above, the present inventors have found that by forming a mixed layer in which a constituent material of a transparent support and a constituent material of an orientation film are mixed with each other to a specific thickness between the support and the orientation film as described above, I found that I could make a film.

The inventor of the present invention has assumed the following reason as to why such an effect can be obtained.

First, when the average SP value of the solvent contained in the coating liquid forming the alignment film is less than 25, the transparent support containing the acrylic resin is dissolved at the time of forming the alignment film, and when the coating liquid is dried, the support shrinks, (See Comparative Examples 4 and 5).

On the other hand, when the average SP value of the solvent contained in the coating liquid forming the alignment film is more than 55, since the transparent support does not dissolve at all, the interface adhesion between the transparent support and the alignment film becomes weak and the alignment film peels off (See Comparative Examples 1 to 3).

Thus, in the present invention, an alignment film is formed using a coating liquid containing a solvent having an average SP value of 25 to 55, whereby the surface of the transparent support is slightly dissolved, and a mixed layer containing a transparent support (acrylic resin) Is formed to have a desired thickness, it can be considered that adhesion is improved while suppressing the generation of wrinkles.

Fig. 1 shows a schematic sectional view of an example of the optical film in the present invention.

The drawings in the present invention are schematic diagrams, and the relationship of the thicknesses of the respective layers and the positional relationships do not always coincide with actual ones. The following drawings are also the same.

The optical film 10 shown in Fig. 1 has a transparent support 16, a mixed layer 15, an orientation film 14, and an optically anisotropic layer 12 in this order.

1 (B), the optical film 10 may have the hard coat layer 18 on the side opposite to the side where the mixed layer 15 of the transparent support 16 is provided, and FIG. 1 The hard coat layer 18 may be provided on the side opposite to the side where the orientation film 14 of the optically anisotropic layer 12 is provided as shown in Fig.

2. Polarizer

The present invention also relates to a polarizing plate (hereinafter simply referred to as "polarizing plate of the present invention") using the optical film of the present invention.

The polarizing plate of the present invention is the polarizing plate having the polarizing film and the optical film of the present invention.

A schematic sectional view of an example of the polarizing plate of the present invention is shown in Fig.

The polarizing plate 20 shown in Fig. 2 (A) has an optically anisotropic layer 12, an orientation film 14, a mixed layer 15, a transparent support 16 and a polarizer 22 in this order.

The polarizing plate 20 shown in Fig. 2B includes a transparent support 16, a mixed layer 15, an orientation film 14, an optically anisotropic layer 12 and a polarizer 22 in this order .

An optional polarizer protective film 24 may be disposed on one surface of the polarizer 22 other than the surface on which the optical film 10 is disposed. Similarly, a polarizer protective film (not shown) may be disposed on the surface of the polarizer 22 where the optical film 10 is disposed, if necessary.

Here, the optically anisotropic layer 12, the orientation film 14, the mixed layer 15 and the transparent support 16 in the polarizing plate 20 are formed by the optical film 10 shown in Fig. 1 (A) 1 (B) and (C). 2 (A), the hard coat layer 18 may be provided on the optically anisotropic layer 12, and in the embodiment shown in Fig. 2 (B), the transparent support 16, The hard coat layer 18 may be provided.

The transparent support 16, the polarizer 22 and the optically anisotropic layer 12 and the polarizer 22 in Fig. 2 (A) in Fig. 2 (A) As shown in Fig.

3. Image display device

The present invention also relates to an image display apparatus (hereinafter also referred to as "image display apparatus of the present invention") using the optical film of the present invention.

An image display apparatus of the present invention is an image display apparatus having an optical film of the present invention, a polarizer, and a liquid crystal cell or an organic EL display panel.

Fig. 3 shows a schematic sectional view of a liquid crystal display device which is an example of the image display device of the present invention.

In the liquid crystal display device 30 shown in Figs. 3A and 3B, the polarizing plate 20 of the present invention is disposed such that the optical film 10 of the present invention is the outermost surface (viewer side).

On the other hand, the liquid crystal display device 30 shown in Figs. 3 (C) and 3 (D) is arranged so that the protective film 24 of the polarizer 22 on the viewing side becomes the outermost layer .

Optional polarizer protective films 36 and 38 are disposed on the front surface and back surface of the backlight side polarizer 34, respectively. The polarizer protective films 34 and 36 may be optical compensation films according to the driving mode of the liquid crystal cell.

Here, the respective layers may be bonded through a pressure-sensitive adhesive or an adhesive agent, not shown.

Fig. 4 shows a schematic sectional view of an organic EL (electroluminescence) display device which is an example of the image display device of the present invention.

The organic EL display device 40 shown in Figs. 4A and 4B includes the polarizing plate 20 of the present invention in which the protective film 24 of the polarizer 22 is arranged to be the outermost layer (visible side) And an organic EL display panel 42.

Here, the respective layers may be bonded through a pressure-sensitive adhesive or an adhesive agent, not shown.

[Optical film]

Hereinafter, various members used in the optical film of the present invention will be described in detail.

[Transparent support]

The transparent support in the optical film of the present invention comprises at least an acrylic resin.

Herein, the term "acrylic resin" refers to a polymer of acrylic acid ester or methacrylic acid ester, and in the following description, it is also referred to as a "(meth) acrylic polymer". Further, the (meth) acrylic polymer is a concept including both a methacrylic polymer and an acrylic polymer.

The content of the acrylic resin in the transparent support is not particularly limited, but it is preferably the main component (more than 50% by mass of the solid content of the transparent support), more preferably 70 to 97% by mass.

In the present invention, acrylic resin or copolymerization components described in paragraphs [0033] to [0063] of Japanese Laid-Open Patent Publication No. 2010-079175 can be suitably used as the acrylic resin.

For example, PMMA (DIANAL BR88, weight average molecular weight: 1,500,000, manufactured by Mitsubishi Rayon Co., Ltd.) and ATON (F5023, manufactured by JSR) can be used as the acrylic resin.

[Mixed layer]

The mixed layer in the optical film of the present invention is a layer in which the constituent material (acrylic resin) of the above-mentioned transparent support and the constituent material of an orientation film described below are mixed.

Here, the existence and thickness of the mixed layer can be confirmed in the following order.

First, a laminate after formation of an orientation film to be described later on a transparent support was cut in the thickness direction with Ultra Microtome EM UC6 manufactured by Leica, Inc. and a diamond knife made by Diatome.

Next, on the cut end face, hydrophilization treatment was carried out with a hydrophilicization device HDT-400 manufactured by Nihon Denshi Datum.

Next, on the section subjected to the hydrophilization treatment, an osmium coating was carried out with a neo-osmium coater made by Meiwa Phoshis Co., Ltd., and observed with a scanning electron microscope (SEM) of S-5500 type manufactured by Hitachi High- , The presence and thickness of the mixed layer can be confirmed (see FIG. 5).

In the present invention, the thickness of the mixed layer is 50 nm to 200 nm, the adhesiveness between the support and the orientation film becomes better, and when used in a stereoscopic image display device, the linearity of the stripe pattern of the patterned optically anisotropic layer becomes good For reasons, it is preferable that it is 80 nm to 150 nm.

In the present invention, the ratio of the constituent material (acrylic resin) of the above-mentioned transparent support in the mixed layer to the constituent material of the orientation film described later is preferably from 1/99 to 99/1, More preferably 90/10.

[Orientation film]

The alignment film in the optical film of the present invention is an alignment film for forming an optically anisotropic layer provided between the transparent support and the optically anisotropic layer.

As described above, the alignment film is formed using a coating liquid containing one or two or more kinds of solvents and having an average SP value of the solvent of 25 to 55. [

Here, the SP value represents the solubility parameter calculated by the Hoy method (Low-molecular Liquid (Solvents)).

The average SP value is an average value of the SP values of the respective solvents in accordance with the mass ratio. Specifically, the average SP value can be calculated using the following formula (I). When only one solvent is used, the average SP value refers to the SP value of the solvent.

[Equation 1]

Si represents the SP value of the i-th solvent, Wi represents the mass fraction of the i-th solvent as the total solvent (mass of the i-th solvent / total mass of the total solvent) .

Here, the solvent having an SP value of 25 to 55 is preferably an alcohol-based solvent, and specific examples thereof include methanol (SP value: 37), ethanol (SP value: 31), n-propyl alcohol (SP value: 27), n-butyl alcohol (hereinafter abbreviated as "n-BuOH") (SP value: 26), isobutyl alcohol (hereinafter abbreviated as "IPA" (SP value: 25), propylene glycol (hereinafter abbreviated as "PG ") (SP value: 32) and the like may be used alone or in combination , Or two or more of them may be used in combination.

In the present invention, when two or more kinds of solvents are used in combination, other solvents which do not satisfy the SP value of 25 to 55 may be used in combination if the SP value of the mixed solvent is 25 to 55. [

Such another solvent is not particularly limited and includes, for example, water [SP value: 72], 2-butanol [SP value: 24], tert-butyl alcohol [SP value: 22] , Methyl ethyl ketone (hereinafter abbreviated as "MEK") (SP value: 22), and the like.

When such other solvent is used, it is preferable that the difference in SP value of each solvent is 50 or less from the viewpoint of compatibility.

In the present invention, the average SP value of the above-mentioned solvent (including the mixed solvent) is preferably 25 to 40 for better adhesion.

The alignment film generally comprises a polymer as a main component. As polymer materials for alignment films, there is a description in many documents, and a large number of commercially available products are available. The polymer material used in the present invention is preferably polyvinyl alcohol or polyimide and derivatives thereof. Particularly, modified or unmodified polyvinyl alcohol is preferable. As the alignment film usable in the present invention, reference can be made to the denatured polyvinyl alcohol described in paragraphs [0071] to [0095] of WO01 / 88574A1, page 43, line 24 to page 49, line 8, and patent 3907735. [

From the standpoint of imparting an orientation ability to form an optically anisotropic layer and relaxing the surface irregularities of the support to form an optically anisotropic layer of uniform thickness, it is preferable that the thickness of the orientation film is small in view of oxygen permeability. Thickness is required. Specifically, the thickness of the alignment film is preferably 0.01 占 퐉 to 10 占 퐉, more preferably 0.01 占 퐉 to 1 占 퐉, and still more preferably 0.01 占 퐉 to 0.5 占 퐉.

In the present invention, it is also preferable to use a photo alignment film. As the photo alignment layer, a polymer material such as a polyamide compound or a polyimide compound described in paragraphs [0024] to [0043] of WO2005 / 096041, and a trade name LPP-JP265CP manufactured by Rolic Technologies can be used.

[Optically anisotropic layer]

The optically anisotropic layer in the optical film of the present invention is an optically anisotropic layer containing a liquid crystalline compound.

<Liquid Crystalline Compound>

In general, the liquid crystalline compound can be classified into a rod type and a disc type from its shape. There are also low molecular weight and polymer types, respectively. Polymer generally refers to polymers having a degree of polymerization of 100 or more (Polymer Physics / Phase Transition Dynamics, Doi Masao, page 2, Iwanami Shoten, 1992). In the present invention, any liquid crystal compound can be used, but it is preferable to use a rod-like liquid crystal compound or a discotic liquid crystal compound (discotic liquid crystal compound). Two or more rod-shaped liquid crystalline compounds, two or more discotic liquid crystalline compounds, or a mixture of rod-shaped liquid crystalline compounds and discotic liquid crystalline compounds may be used. In order to immobilize the liquid crystalline compound described above, it is more preferable to use a rod-shaped liquid crystalline compound having a polymerizable group or a discotic liquid crystalline compound, and it is more preferable that the liquid crystalline compound has two or more polymerizable groups in one molecule desirable. When the liquid crystalline compound is a mixture of two or more kinds, it is preferable that at least one liquid crystalline compound has two or more polymerizable groups in one molecule.

As the rod-shaped liquid crystalline compound, those described in paragraphs [0026] to [0098] of Japanese Patent Publication No. 11-513019 or Japanese Patent Laid-Open Publication No. 2005-289980 can be preferably used, As the liquid crystal compound, those described in paragraphs [0020] to [0067] of Japanese Patent Application Laid-Open No. 2007-108732 and paragraphs [0013] to [0108] of Japanese Laid-Open Patent Publication No. 2010-244038 can be preferably used , But are not limited thereto.

<Orientation>

It is preferable that the molecules of the liquid crystal compound are immobilized in any one of the vertical alignment, horizontal alignment, hybrid alignment, and oblique alignment.

Herein, the hybrid orientation means that the angle between the molecular symmetry axis and the layer plane of the molecule of the discotic liquid crystalline compound, or the molecule of the discotic liquid crystalline compound, in the depth direction of the optically anisotropic layer and the distance from the surface of the orientation film And the orientation is increasing or decreasing with increasing.

Preferably, the angle increases with increasing distance.

Also, as the change of the angle, it is possible to make intermittent changes including continuous increase, continuous decrease, intermittent increase, intermittent decrease, change including continuous increase and continuous decrease, or increase and decrease. The intermittent change includes a region where the inclination angle does not change in the middle of the thickness direction.

In addition, although the angle includes an area where the angle does not change, it is preferable that the angle is continuously changed, though it may be increased or decreased as a whole. Of course, it may be uniformly uniformly inclined.

As a mode in which the liquid crystalline compound is immobilized in such a hybrid alignment state, for example, an embodiment is used as an optical compensation film of a twist alignment mode liquid crystal display device, and specifically, 0123] to [0126] can be preferably used, but the present invention is not limited thereto.

On the other hand, in order to make the optically anisotropic layer function as the? / 4 plate, the orientation state of the liquid crystalline compound may be controlled.

Here, the? / 4 plate (plate having a? / 4 function) is a plate having a function of converting linearly polarized light of a specific wavelength into circularly polarized light (or circularly polarized light into linearly polarized light). More specifically, the in-plane retardation value at a predetermined wavelength? Nm is? / 4 (or an odd multiple thereof).

When the lambda / 4 plate has a single-layer structure, the angle formed by the absorption axis of the polarizer and the in-plane slow axis of the lambda / 4 plate is preferably 45 DEG. In the case of a structure in which a plurality of layers are laminated, Axis relationship can be adopted.

As a mode in which the? / 4 plate has a single-layer structure, for example, a stretched polymer film or a retardation film provided with an optically anisotropic layer having a? / 4 function on a support can be given.

As a mode in which the? / 4 plate has a multi-layer structure, for example, a wide-band? / 4 plate formed by laminating a? / 4 plate and a? / 2 plate is exemplified. It is also preferable that the in-plane slow axis of the? / 4 plate and the in-plane slow axis of the? / 2 plate are 60 degrees in the wide-band? / 4 plate.

The material constituting the lambda / 4 plate is not particularly limited as long as it exhibits the above characteristics, and as described with respect to the optically anisotropic layer described above, a mode including a liquid crystal compound (for example, an optical anisotropy including a homogeneous liquid crystal compound Layer), a polymer film, and the like. Among them, it is preferable to include a liquid crystalline compound in view of easy control of the characteristics. More specifically, the? / 4 plate is preferably a layer in which a liquid crystal compound having a polymerizable group (a rod-like liquid crystal compound or a discotic liquid crystal compound) is fixed and fixed by polymerization or the like. In this case, Is no longer required to exhibit liquid crystallinity.

In this case, when the rod-like liquid crystalline compound is used, it is preferable to immobilize the rod-like liquid crystalline compound in a horizontally aligned state. When the discotic liquid crystal compound is used, the discotic liquid crystal compound is vertically aligned It is preferable to fix it. In the present invention, the term "horizontal orientation of the rod-like liquid crystalline compound" means that the director and the layer plane of the rod-like liquid crystalline compound are parallel to each other, and "the vertical orientation of the discotic liquid crystalline compound" Refers to the fact that the source side and the layer side of the compound are perpendicular to each other. It is assumed that they are within a range of ± 20 ° from an accurate angle, not strictly horizontal or vertical. More preferably within ± 5 °, more preferably within ± 3 °, even more preferably within ± 2 °, most preferably within ± 1 °.

An additive (alignment control agent) for promoting horizontal alignment and vertical alignment may be used in order to bring the liquid crystal compound into a horizontal alignment and a vertical alignment state. As the additive, various known ones can be used.

The method of forming the? / 4 plate is not particularly limited and a known method can be employed. For example, a method of forming the above-described first optically anisotropic layer (a method of using a composition containing a liquid crystal compound having a polymerizable group Method).

<Retardation>

The retardation of the optical film of the present invention is not particularly limited as it depends on the use of the image display apparatus to be used, but it is preferable that the in-plane retardation at a wavelength of 550 nm is 40 nm to 240 nm.

Particularly, in an image display apparatus, it is preferable that the optically anisotropic layer has a retardation region with a phase difference of about? / 4, because it can be brought close to an accurate circularly polarized light. Specifically, an in-plane retardation value Re (550) at a wavelength of 550 nm may have an error of about 25 nm centering on an ideal value (137.5 nm), for example, more preferably 110 nm to 165 nm More preferably from 115 nm to 150 nm, and particularly preferably from 120 nm to 145 nm.

When the optical film of the present invention functions as a wide-band? / 4 plate formed by laminating a? / 4 plate having a multilayer structure, for example, the? / 4 plate and the? / 2 plate described above, The in-plane retardation value Re (550) at the wavelength of 550 nm of the optically anisotropic layer corresponding to the plate may have an error of about 25 nm centering on the ideal value (275 nm), for example, More preferably 260 nm to 290 nm.

On the other hand, when the optical film of the present invention is used for an optical compensation film of a TN mode liquid crystal cell, it is preferable that the in-plane retardation at a wavelength of 550 nm is 40 nm to 80 nm.

<Thickness>

In the present invention, the thickness of the optically anisotropic layer is not particularly limited, but it is preferably 0.1 m to 10 m, more preferably 0.5 m to 5 m.

&Lt; Pattern optically anisotropic layer &

In the present invention, at least one of the in-plane slow axis direction and the in-plane retardation is used for the reason that the optically anisotropic layer produces right-handed circularly polarized light and left-handed circularly polarized light and can be suitably used for a stereoscopic image display device It is preferable that the patterned optically anisotropic layer has two or more different retardation regions. More specifically, it is preferable that at least one of the in-plane slow axis direction and the in-plane retardation includes a first retardation region and a second retardation region, And the second retardation region are pattern optically anisotropic layers arranged alternately in the plane.

Figs. 6 (A) to 6 (C) show a schematic front view of an example of the patterned optically anisotropic layer.

For example, the optically anisotropic layer 12 shown in Figs. 6 (A) to 6 (C) includes a first retardation region 12a and a second retardation region 12b in which at least one of the in- And the first retardation region 12a and the second retardation region 12b are alternately arranged in the plane. The first retardation region 12a and the second retardation region 12b have in-plane slow axes a and b perpendicular to each other.

The shapes and arrangement patterns of the first retardation region 12a and the second retardation region 12b in the optically anisotropic layer 12 are the same as those shown in Figs. Alternatively, as shown in Fig. 6 (C), rectangular patterns may be arranged in a lattice pattern.

7, the polarizing plate 20 (circularly polarizing plate) is arranged between the first retardation region 12a in the optically anisotropic layer 12 and the second retardation region 12b in the optically anisotropic layer 12, The first retardation region 12a and the second retardation region 12b are formed with respect to the optical film 10 in which the retardations of the second retardation regions 12b are each about? / 4 and the directions of the slow axes a and b are different by 90 占The slow axes a and b of the first retardation film 12b and the absorption axis 23 of the polarizer 22 intersect each other at 45 degrees b are respectively set to 45 deg., the absorption axis 23 of the polarizer 22 is 0 deg.).

As the method of forming the above-described patterned optically anisotropic layer, the following preferable embodiments are exemplified, but the present invention is not limited thereto and can be formed by various known methods.

The first preferred embodiment is a method in which a plurality of operations for controlling the orientation of the liquid crystalline compound are used and then an action is exerted by external stimulation (such as heat treatment) to dominate the predetermined orientation control action to be. In the above method, for example, the liquid crystalline compound is brought into a predetermined alignment state by the combined action of the alignment control ability by the alignment film and the alignment control ability of the alignment control agent added to the liquid crystal compound, (For example, action by the alignment control agent) is lost by the external stimulus (heat treatment or the like) after forming one phase difference region, and the other alignment control action Thereby realizing another orientation state and fixing it to form the other retardation region. Details of this method are described in paragraphs [0017] to [0029] of Japanese Laid-Open Patent Publication No. 2012-008170, the contents of which are incorporated herein by reference.

The second preferred embodiment is an aspect using a pattern alignment film. In this embodiment, a pattern alignment film having different alignment control ability is formed, and a liquid crystal compound is arranged thereon to align the liquid crystal compound. The liquid crystal compound achieves different alignment states by the orientation control ability of each of the pattern alignment films. By fixing the respective alignment states, patterns of the first and second retardation regions are formed according to the pattern of the alignment film. The pattern alignment film can be formed by using a printing method, mask rubbing for a rubbing alignment film, mask exposure for a photo alignment film, or the like. A method using a printing method is preferable because a large-scale facility is unnecessary or a manufacturing is easy. Details of this method are described in paragraphs [0166] to [0181] of Japanese Laid-Open Patent Publication No. 2012-032661, the contents of which are incorporated herein by reference.

As a third preferred embodiment, for example, the photoacid generator is added to the alignment film. In this example, a photoacid generator is added to the alignment film, and the region where the photoacid generator is decomposed and the acid compound is generated and the region where the acidic compound is not generated are formed by pattern exposure. The photoacid generator is almost undifferentiated in the part of the tail light irradiation, and the interaction between the alignment film material, the liquid crystal compound and the alignment controller added as needed dominates the alignment state, and the liquid crystal compound is rubbed Direction in a direction orthogonal to the direction. When an acid compound is generated by light irradiation with an alignment film, the interaction is not already dominant, the rubbing direction of the rubbing alignment film dominates the alignment state, and the liquid crystal compound is aligned in parallel with the rubbing direction do. As the photoacid generator used in the alignment film, a water-soluble compound is preferably used. Examples of photoacid generators that can be used include those described in Prog. Polym. Sci., 23, 1485 (1998). As the photoacid generator, pyridinium salts, iodonium salts and sulfonium salts are particularly preferably used. Details of this method are described in Japanese Patent Application No. 2010-289360, the content of which is incorporated herein by reference.

[Other layers, optional components]

<Hard coat layer>

In the optical film of the present invention, it is preferable that a hard coat layer is provided to impart physical strength of the film. Specifically, it may have a hard coat layer on the side opposite to the side where the alignment film of the transparent support is provided (see Fig. 1 (B)), or may have a hard coat layer on the side opposite to the side where the alignment film of the optically anisotropic layer is provided (See Fig. 1 (C)).

As the hard coat layer, those described in paragraphs [0190] to [0196] of Japanese Laid-Open Patent Publication No. 2009-98658 can be used.

<Ultraviolet absorber>

The optical film of the present invention preferably contains an ultraviolet (UV) absorber in consideration of the influence of external light (particularly ultraviolet light), and more preferably includes an ultraviolet absorber in the transparent support.

As the ultraviolet absorber, ultraviolet absorptivity can be exhibited, and any known one can be used. Among such ultraviolet absorbers, a benzotriazole-based or hydroxyphenyltriazine-based ultraviolet absorber is preferable in order to obtain ultraviolet absorptivity (ultraviolet light shielding ability) which is high in ultraviolet absorptivity and used in an electronic image display apparatus. In order to widen the absorption width of ultraviolet rays, two or more ultraviolet absorbers having different maximum absorption wavelengths may be used in combination.

[Production method of optical film]

The production method for producing the optical film of the present invention is characterized in that a coating liquid containing one or more kinds of solvents and having an average SP value of the solvent of 25 to 55 is applied on a transparent support containing an acrylic resin, A mixed layer / orientation film forming step of forming a mixed layer in which a constituent material of the transparent support and a constituent material of the orientation film are mixed between the transparent support and the orientation film,

An optically anisotropic layer forming step of forming an optically anisotropic layer on an alignment film by using a composition for forming an optically anisotropic layer containing a liquid crystal compound to produce an optical film.

Here, the transparent support, the coating liquid for forming an alignment film, and the solvent and the liquid crystal compound are the same as those described in the optical film of the present invention described above.

[Mixed layer / alignment layer forming step]

The mixing layer / orientation film forming step is not particularly limited as long as it is formed using a coating liquid containing one or two or more kinds of solvents and having an average SP value of the solvent of 25 to 55. For example, A polymer material for an alignment film, or the like is applied on a transparent support and dried.

In the present invention, the solid content concentration of the coating liquid is preferably 60 mass% or less, and more preferably 30 to 55 mass%, for the reason of excellent coating property.

<Optically Anisotropic Layer Forming Step>

The optically anisotropic layer forming step includes, for example, a method of immobilizing the liquid crystalline compound in an aligned state. At this time, as a method for immobilizing the liquid crystalline compound, a method of polymerizing and fixing the liquid crystalline compound using a liquid crystalline compound having a polymerizable group is suitably exemplified. The optically anisotropic layer may have a single layer structure or a laminate structure.

[Polarizer]

Hereinafter, various members used in the polarizing plate of the present invention will be described in detail.

Here, the polarizing plate of the present invention has the above-mentioned optical film of the present invention and a polarizer.

[Polarizer]

As the polarizer, a general polarizer can be used. As the polarizer usable in the present invention, for example, a polarizer made of iodine or a polyvinyl alcohol film stained by a dichroic dye can be used.

[Pressure-sensitive adhesive layer]

A pressure-sensitive adhesive layer may be disposed between the optically anisotropic layer and the polarizer. As the pressure-sensitive adhesive layer used for lamination of the optically anisotropic layer and the polarizer, for example, the ratio of the storage elastic modulus G 'to the loss elastic modulus G "(tan δ = G" / G') measured by a dynamic viscoelasticity measuring device is 0.001 to 1.5 , And includes so-called pressure-sensitive adhesives, substances which are liable to creep, and the like. Examples of the pressure-sensitive adhesive that can be used in the present invention include, but are not limited to, a polyvinyl alcohol-based pressure-sensitive adhesive.

[Image display device]

Hereinafter, various members used in the image display apparatus of the present invention will be described in detail.

Here, the image display apparatus of the present invention is an image display apparatus having the above-described optical film of the present invention, a polarizer, a liquid crystal cell or an organic EL display panel.

In the present invention, the order of the layer constitution in the image display device is not particularly limited, and may be an aspect in which an optical film, a polarizer, and a liquid crystal cell are provided in this order from the viewing side. A film, a liquid crystal cell, or an organic EL display panel in this order.

In the embodiment having a polarizer for image display on the viewer side of the image display panel, such as a liquid crystal panel in a transmission mode, the polarizer is used as a polarizer in the polarizing plate of the present invention, It is also preferable that the polarizing plate of the viewer side also serves as a polarizing plate.

[Liquid crystal display device]

As a liquid crystal display device which is an example of the image display device of the present invention, for example, a mode in which the optical film of the present invention, the polarizer, and the liquid crystal cell are arranged in this order (Figs. 3 (C) and 3 (D)) having a polarizer, an optical film of the present invention and a liquid crystal cell in this order from the viewing side.

<Liquid crystal cell>

The liquid crystal cell used in the image display apparatus (liquid crystal display device) of the present invention is preferably VA mode, OCB mode, IPS mode, or TN mode, but is not limited thereto.

In the TN mode liquid crystal cell, the rod-like liquid crystalline molecules are substantially horizontally aligned at a voltage-free state, and further torsionally oriented at 60 to 120 degrees. The TN mode liquid crystal cell is most often used as a color TFT liquid crystal display device, and is described in a large number of documents.

In the VA mode liquid crystal cell, the rod-shaped liquid crystalline molecules are oriented substantially vertically when no voltage is applied. The liquid crystal cell of the VA mode includes (1) a liquid crystal cell of a VA mode in a narrow sense in which the rod-shaped liquid crystalline molecules are oriented substantially vertically when voltage is not applied and substantially horizontally aligned when a voltage is applied (MVA mode) liquid crystal cell (SID97, Digest of tech. Papers 28 (1997) 845) in which a VA mode is made into a multi-domain, in addition to (2) ), (3) a liquid crystal cell in a mode (n-ASM mode) in which rod-shaped liquid crystalline molecules are vertically aligned substantially vertically when voltage is applied and torsion multi-domain is oriented when voltage is applied (1998)), and (4) liquid crystal cells of the SURVIVAL mode (disclosed in LCD International 98). In addition, any of PVA (Patterned Vertical Alignment) type, optical alignment type (Optical Alignment) and PSA (Polymer-Sustained Alignment) may be used. Details of these modes are described in Japanese Laid-Open Patent Publication No. 2006-215326 and Japanese Laid-Open Patent Publication No. 2008-538819.

In the IPS mode liquid crystal cell, the rod-like liquid crystal molecules are oriented substantially parallel to the substrate, and the liquid crystal molecules respond in a planar manner by applying an electric field parallel to the substrate surface. In the IPS mode, black display is performed in the absence of an electric field, and the absorption axes of the upper and lower pairs of polarizing plates are orthogonal. A method of improving the viewing angle by reducing the leakage light in black display in the oblique direction using the optical compensation sheet is disclosed in Japanese Unexamined Patent Publication No. 10-54982, Japanese Unexamined Patent Application Publication No. 11-202323, Japanese Patent Application Laid-Open Nos. 9-292522, 11-133408, 11-305217, 10-307291, etc.

[Organic EL display device]

As the organic EL display device which is an example of the image display device of the present invention, for example, as described above, a mode having the polarizer, the optical film of the present invention, and the organic EL display panel in this order from the viewer side (Fig. 4).

Here, the organic EL display panel is a display panel configured by using an organic EL element in which an organic light emitting layer (organic electroluminescence layer) is sandwiched between electrodes (between a cathode and an anode).

The configuration of the organic EL display panel is not particularly limited, and a known configuration is employed.

Example

Hereinafter, the present invention will be described in more detail based on examples. The materials, the amounts used, the ratios, the processing contents, the processing procedures, and the like shown in the following examples can be appropriately changed without departing from the gist of the present invention. Therefore, the scope of the present invention should not be construed to be limited by the following embodiments.

[Example 1]

&Lt; Production of optical film &

(Dope preparation)

Each component of the following composition was charged into a mixing tank and stirred with heating to dissolve each component to prepare a dope.

-─ ------------------------------------------------ --------------------

Dope composition

-─ ------------------------------------------------ --------------------

PMMA resin (DIANAL BR88, weight average molecular weight: 1500000, manufactured by Mitsubishi Rayon Co., Ltd.) 100 parts by mass

· Water permeability reducing compound (B-7) 10 parts by mass

Ultraviolet absorber (Tinuvin 328, manufactured by Chiba Specialty Chemicals) 2.4 parts by mass

Brittle modifier (LA4285, manufactured by Kuraray Co., Ltd.) 5.0 parts by mass

Dichloromethane 534 parts by mass

· Methanol 46 parts by mass

-─ ------------------------------------------------ --------------------

[Chemical Formula 1]

(Production of transparent support)

The dope prepared by using a band casting device was uniformly inflexible from a flexible die to a stainless steel endless band (flexible support) with a width of 2000 mm.

When the amount of the residual solvent in the dope becomes 15 mass%, it is peeled off as a polymer film from the flexible support, and is transported without being actively stretched with a tenter, and drying is carried out at 120 캜 in a drying zone to produce a transparent support containing an acrylic resin did.

(Preparation of a transparent support having an alignment film before exposure)

On the prepared transparent support, the alignment film coating liquid of the following composition was applied directly to the wire of # 14. After drying at 25 DEG C for 30 seconds, the resultant was further placed in an oven at 125 DEG C for 100 seconds to form a transparent support having an alignment film with an alignment film. The film thickness of the alignment film was 0.49 μm.

-------------------------------------------------- -----------------

Composition of alignment film coating liquid 1

-------------------------------------------------- -----------------

Polymer (PVA) material (P-1) 2.50 parts by mass

- Photo acid generator (S-1) 0.20 parts by mass

Radical polymerization initiator (Irgacure 2959, manufactured by Chiba Specialty Chemicals) 0.18 parts by mass

· Methanol 43.40 parts by mass

IPA (isopropanol) 10.32 parts by mass

·pure 43.40 parts by mass

-------------------------------------------------- -----------------

(2)

(Ultraviolet ray exposure)

The orientation film was subjected to one round-trip rubbing treatment in one direction at 900 rpm while maintaining an angle of 45 degrees with respect to the stripe of the stripe mask.

Next, a stripe mask having a transverse stripe width of 363 占 퐉 and a transverse stripe width of 363 占 퐉 of the shielding portion was disposed on the above-prepared transparent support with the pre-exposure alignment film prepared thereon, and an illuminance of 500 mW / cm ² using a UV irradiation apparatus (light Hammer 10, 240W / cm , Fusion UV Systems , Inc.) as the light source unit is irradiated with ultraviolet rays (30mJ / cm ²⁾ 0.06 seconds, to form an alignment film pattern.

(Formation of pattern optically anisotropic layer)

Next, the following coating liquid for optically anisotropic layer was applied directly to wire # 3.2. Also, after one minutes heat aging at a film surface temperature of 115 ℃, air-cooled metal halide lamp of 20mW / cm ² under cooling and air to 90 ℃ using (I Graphics Co., Ltd.) and irradiated with ultraviolet rays 20 seconds, fixing the oriented state Thereby forming a patterned optically anisotropic layer, thereby producing an optical film. The discotic liquid crystal compound was vertically aligned in the slow axis direction with respect to the rubbing direction and the unexposed portion (second retardation region) was perpendicularly oriented perpendicularly to the rubbing direction in the mask exposed portion (first retardation region). The film thickness of the optically anisotropic layer was 1.16 占 퐉.

-------------------------------------------------- -----------------

Composition of optically anisotropic layer coating liquid 1

-------------------------------------------------- -----------------

· Discotic liquid crystal E-2 80 parts by mass

· Discotic liquid crystal E-3 20 parts by mass

Alignment film interface orientation agent (II-1) 0.9 parts by mass

· Alignment film interface orientation agent (III-1) 0.08 parts by mass

· Air Interface Orientation Agent (P-2) 0.2 parts by mass

· Air Interface Orientation Agent (P-3) 0.6 parts by mass

Photopolymerization initiator (Irgacure 907, BASF) 3.0 parts by mass

· Polyfunctional monomer (ethylene oxide modified trimethylol propyl acrylate (Viscot 360, made by Osaka Yuki Kagaku)) 10 parts by mass

· Methyl ethyl ketone 268 parts by mass

-------------------------------------------------- -----------------

(3)

[Examples 2 to 7 and Comparative Examples 1 to 5]

An optical film was produced in the same manner as in Example 1 except that the composition and the amount of the solvent in the composition of the alignment film coating liquid were changed to those shown in Table 1 below.

[Referential Example 1]

An optical film was produced in the same manner as in Example 1 except that the transparent support was changed to a TAC film produced by the following method.

(1) Preparation of Dope 1 for core layer

A dope for core layer having the following composition was prepared.

-------------------------------------------------- -----------------

Composition of dope

-------------------------------------------------- -----------------

Cellulose acetate (acetylation degree 2.86, number average molecular weight 72000) 100 parts by mass

Methylene chloride (first solvent) 320 parts by mass

Methanol (second solvent) 83 parts by mass

· 1-Butanol (third solvent) 3 parts by mass

· Triphenyl phosphate 8.3 parts by mass

· Biphenyldiphenylphosphate 4.2 parts by mass

Compound 1 0.98 parts by mass

Compound 2 0.24 parts by mass

-------------------------------------------------- -----------------

[Chemical Formula 4]

Specifically, it was prepared by the following method.

The first solvent, the second solvent and the third solvent were added to a 4000 L stainless steel dissolution tank having a stirring blade, and after sufficiently stirring, cellulose acetate powder (flake), triphenylphosphate, biphenyldiphenylphosphate, compound 1 And Compound 2 were gradually added to prepare a solution having a total weight of 2000 kg.

The dissolving tank is equipped with a dissolver type eccentric stirring shaft in which a stirring shear speed is initially stirred at a peripheral speed of 5 m / sec, and an anchor blade at a central axis and having a peripheral speed of 1 m / sec (shear stress: 1 x 10 ⁴ kgf / m / sec ² ) for 30 minutes. After completion of the dispersion, the high-speed stirring was stopped, the peripheral speed of the anchor blade was set at 0.5 m / sec, and further stirred for 100 minutes.

A solution swollen with the cellulose acetate powder was pumped from the dissolution tank into the jacket mounting pipe. Next, the jacket mounting pipe was heated to 50 占 폚 and further heated to 90 占 폚 by pressurization of 2 MPa to be completely dissolved. The heating time was 15 minutes.

Next, the temperature was lowered to 36 占 폚, and a filter medium having a nominal pore diameter of 8 占 퐉 was passed through to obtain a dope.

The condensation dope thus obtained was flashed in a flash device adjusted to normal pressure at 80 DEG C, and the evaporated solvent was collected and collected in a condenser. The solid content concentration of the dope after flash was 21.8 mass%. The flash tank of the flash device was degassed by stirring at a peripheral speed of 0.5 m / sec using an anchor blade having a central axis. The temperature of the dope in the tank was 25 DEG C and the average residence time in the tank was 50 minutes.

Subsequently, air bubbles were removed by irradiating the dope with weak ultrasonic waves. Thereafter, in a state of being pressurized to 1.5 MPa, a sintered fiber metal filter having a nominal pore diameter of 10 m was first passed, and then a sintered fiber filter of 10 m was passed through the same. The dope temperature after filtration was adjusted to 36 캜 and stored in a 2000 L stock tank made of stainless steel. The stock tank was always stirred at a peripheral speed of 0.3 m / sec using an anchor blade having a central axis, thereby obtaining a dope for core layer.

(2) Preparation of Dope 1-a for Support Layer

(Dibutyl phthalate), a matting agent (silicon dioxide (particle diameter 20 nm)) and a peeling accelerator (citric acid ethyl ester (citric acid, monoethyl ester, diethyl ester, triethyl ester mixture)) and a core layer Doping 1 were mixed via a static mixer, 1-a. The addition amount was such that the total solid content concentration was 20.5 mass%, the mat agent concentration was 0.05 mass%, and the peel promoter concentration was 0.03 mass%.

(3) Preparation of air layer 1-b

And a matting agent (silicon dioxide (particle diameter: 20 nm)) were mixed with the above-mentioned core layer-forming dope 1 through a static mixer to prepare an air layer-use dope 1-b. The addition amount was such that the total solid concentration was 20.5 mass% and the mat agent concentration was 0.1 mass%.

(4) Coating by coalescence

As a flexible die, a device was used in which a feed block adjusted to a common continuous length was provided and laminated on both sides in addition to the mainstream to form a film having a three-layer structure. In the following description, the layer formed by the mainstream is referred to as a core layer, the layer on the side of the support surface is referred to as a support layer, and the surface on the opposite side is referred to as an air layer. In addition, the feed flow path of the dope used 3 flow paths for the core layer, the support layer, and the air layer.

The dope for the core layer, the dope 1-a for the support layer and the dope 1-b for the air layer were jointly fired on a drum cooled to -5 ° C from the oil study. At this time, the flow rate of each dope was adjusted so that the ratio of the thickness of the air layer / core layer / support layer = 3/54/3. The flexible dope film was dried by applying dry air at 34 ° C at 230 m ³ / min on the drum, and the drum was peeled off with the residual solvent at 150%. At the time of peeling, 17% of stretching was performed in the transport direction (longitudinal direction). Thereafter, both ends of the film in the width direction (direction orthogonal to the flexible direction) were transported while being gripped by a pin tenter (a pin tenter shown in Fig. 3 of JP-A-4-1009). Further, the film was further dried by transporting between rolls of the heat treatment apparatus to produce a TAC film having a film thickness of about 60 탆.

[Reference Example 2]

An optical film was produced in the same manner as in Example 1 except that the transparent support was changed to a PET film produced by the following method.

(Production of PET film)

90 parts by mass of the polyester resin pellets containing no particles as the raw material for the base film were dried under reduced pressure (1 Torr) at 135 캜 for 6 hours, and then supplied to an extruder to be melted at 285 캜. This polymer was filtered through a filter material (nominal pore diameter 10 μm particle size 95% cut) of a stainless steel sintered body and extruded into a sheet form from a mouthpiece and wound around a casting drum having a surface temperature of 30 ° C. by electrostatic casting And solidified to produce an unoriented film.

The unstretched film was led to a tenter stretching machine and led to a hot air zone at a temperature of 125 캜 while gripping an end portion of the film with a clip, and stretched 4.0 times in the width direction. Next, the uniaxially oriented PET film having a film thickness of about 50 占 퐉 was obtained by treating the film at a temperature of 225 占 폚 for 30 seconds while maintaining the stretched width in the width direction, and further performing a relaxation treatment of 3% in the width direction.

[Example 8]

An optical film was produced in the same manner as in Example 1 except that the formation of an orientation film and the formation of an optically anisotropic layer were changed to the contents shown below.

(Formation of alignment film)

The alignment film coating liquid of the following composition was applied at 28 mL / m ² using a # 16 wire bar coater. And then dried with warm air at 60 DEG C for 60 seconds and further with hot air at 90 DEG C for 150 seconds to prepare an orientation film.

-------------------------------------------------- ---------------------

Composition of alignment film coating liquid 2

-------------------------------------------------- ---------------------

Modified polyvinyl alcohol represented by the following formula 10 parts by mass

· IPA 490 parts by mass

Glutaraldehyde (crosslinking agent) 0.5 parts by mass

· Citric acid ester (AS3, manufactured by Sankyo Chemical Industry Co., Ltd.) 0.35 parts by mass

-------------------------------------------------- ---------------------

[Chemical Formula 5]

And dried at 25 DEG C for 60 seconds, 60 DEG C for 60 seconds, and further at 90 DEG C for 150 seconds. The thickness of the alignment film after drying was 1.1 mu m.

(Rubbing treatment)

The formed alignment film was transported at a speed of 20 m / min, and a rubbing roll (300 mm in diameter) was set so that the film was rubbed in the longitudinal direction, and the film was rotated at 650 rpm to rub the surface of the cellulose acylate film provided with the alignment film.

(Formation of optically anisotropic layer)

Next, on the alignment film, the coating liquid containing the discotic liquid crystal having the following composition was rotated in the same direction as the film conveying direction by 391 rotations of the # 2.8 wire bar to form an alignment film on the alignment film surface conveyed at 20 m / And continuously applied.

-------------------------------------------------- ---------------------

Composition of optically anisotropic layer coating liquid 2

-------------------------------------------------- ---------------------

The discotic liquid crystal compound (D) shown in the following structural formula (C) 91 parts by mass

Fluorine-based polymer A having the following structure 4 parts by mass

· Ethylene oxide modified trimethylol propane triacrylate (V # 360, made by Yuki Kagaku) 9 parts by mass

· Sensitizer (Kayacure DETX, made by Nippon Kayaku) 1 part by mass

Photopolymerization initiator (Irgacure 907, made by Chiba Chemical Co.) 3 parts by mass

· Methyl ethyl ketone 212 parts by mass

-------------------------------------------------- ---------------------

[Chemical Formula 6]

Next, in the step of heating continuously from room temperature to 100 占 폚, the solvent is dried and then heated for about 90 seconds so that the surface velocity of the discotic liquid crystal compound layer becomes 2.5 m / sec in a drying zone at 130 占 폚 , And the discotic liquid crystal compound was aligned.

Then, ultraviolet rays were irradiated for 4 seconds by the ultraviolet ray irradiation apparatus (ultraviolet lamp: output 120 W / cm) in the state that the surface temperature of the film was about 130 占 폚, and the crosslinking reaction was progressed so that the discotic liquid crystal compound was oriented .

[Example 9]

An optical film was produced in the same manner as in Example 8 except that the formation of the optically anisotropic layer was changed to that shown below.

(Formation of optically anisotropic layer)

The alignment film was continuously rubbed. At this time, the longitudinal direction and the transport direction of the elongated film were parallel to each other, and the rotation axis of the rubbing roller with respect to the longitudinal direction of the film was rotated clockwise by 45 degrees.

A coating liquid containing the discotic liquid crystal compound of the following composition was applied continuously onto the alignment layer formed above with a wire of # 2.7. The transport speed V of the film was 36 m / min. For drying of the solvent of the coating liquid and aging of the discotic liquid crystal compound, heating was conducted for 90 seconds with hot air at 80 캜. Then, the film was subjected to UV irradiation at 80 占 폚 to fix the alignment of the liquid crystal compound to form an optically anisotropic layer, thereby obtaining an optical film.

-------------------------------------------------- ---------------------

Composition of optically anisotropic layer coating liquid 3

-------------------------------------------------- ---------------------

The following discotic liquid crystal compound 100 parts by mass

Photopolymerization initiator (Irgacure 907, manufactured by Chiba Japan) 3 parts by mass

· Sensitizer (Kayacure DETX, made by Nippon Kayaku) 1 part by mass

The following pyridinium salts 1 part by mass

The following fluoropolymer (FP1) 0.4 parts by mass

· Methyl ethyl ketone 252 parts by mass

-------------------------------------------------- ---------------------

(7)

[Example 10]

An optical film was produced in the same manner as in Example 1 except that the formation of the optically anisotropic layer was changed to that shown below.

(Formation of optically anisotropic layer)

The coating liquid for the optically anisotropic layer of the following composition was continuously applied on the surface of the alignment film of the film conveyed at 10 m / min by rotating the # 3.2 wire bar in the same direction as the film conveying direction by 391 rotations. The coating amount was 4 ml / m ² . The inside of the heating zone at 80 캜 was conveyed and dried at a film surface temperature of 80 캜 for one minute to form a coated liquid crystal state, uniformly oriented, and cooled to room temperature.

Finally, the film was taken up into a cylindrical shape to obtain a roll-shaped optical film. The slow axis of the first retardation region and the slow axis of the second retardation region were orthogonal to each other, and the film thickness was 0.9 占 퐉. Only the optically anisotropic layer was peeled from the optical film and the average direction of the molecular symmetry axis of the optically anisotropic layer was measured and found to be 45 DEG with respect to the longitudinal direction of the optical film.

-------------------------------------------------- ---------------------

Composition of optically anisotropic layer coating liquid 4

-------------------------------------------------- ---------------------

· Bar-shaped liquid crystal (I-27) 100 parts by mass

Horizontal alignment agent (A) 0.3 parts by mass

Photopolymerization initiator (Irgacure 907, BASF) 3.3 parts by mass

· Sensitizer (Kayacure DETX, made by Nippon Kayaku) 1.1 parts by mass

· Methyl ethyl ketone 300 parts by mass

-------------------------------------------------- ---------------------

[Chemical Formula 8]

[Example 11]

An optical film was produced in the same manner as in Example 1, except that the formation of the orientation film was changed to the following contents.

(Production of transparent support having a photo alignment layer)

On the transparent support prepared in Example 1, the photo-alignment material having the following structure was dissolved in IPA at 1%, and the wire was continuously and directly applied. And dried in hot air at 100 DEG C for 60 seconds to form a photo alignment film. The film thickness of the alignment film was 0.1 mu m.

[Chemical Formula 9]

(Photo-alignment treatment)

The support on which the photo alignment layer was formed was transported at a speed of 10 m / min, and irradiated with polarized ultraviolet rays of 1000 mW / cm ² for 0.1 second through an exposure slit provided on the substrate at a distance of 10 mm to give a photo-alignment function for the first retardation region did. Further, the polarization axis of the polarized light exposure was set at 45 DEG with respect to the conveying direction.

Subsequently, the sheet was successively conveyed onto a roller (drum) serving as a pedestal of pattern exposure with conveyance rollers provided before and after. On a roller serving as a pedestal, a photomask having a slit engraved at a pitch of 200 mu m in a direction parallel to the conveying direction and an exposure slit provided at a position of 10 mm on the substrate in parallel with the photomask were formed on a support member having a photo- / cm &lt; ² &gt; for 0.4 seconds to give a photo-alignment function for the second retardation region. The stripe shape of the photomask is parallel to the transport direction, that is, the transparent portion of the photomask and the shielding portion are alternately arranged in the direction orthogonal to the transport direction. The polarizing axis of the polarized light exposure was -45 占 with respect to the conveying direction, and the roller serving as a pedestal was controlled to have a temperature control function by water cooling so that the support temperature was 40 占 폚 or less throughout the entire exposure process. During the exposure, the support was kept pressed on the roller.

[Example 12]

On the optically anisotropic layer-formed surface of the optical film produced in Example 1, the following flash-resistant hard coat layer was formed.

(Repellent hard coat layer)

Each component was mixed with a mixed solvent of MIBK (methyl isobutyl ketone) and MEK (methyl ethyl ketone) (89 to 11 (mass ratio)) so that the following composition was obtained. And filtered through a polypropylene filter having a pore diameter of 30 탆 to prepare a water repellent hard coat layer coating liquid 1. The solid concentration of each coating liquid is 40 mass%. Further, in the preparation of the coating liquid, the resin particles and smectite were added in a dispersion state described later.

-------------------------------------------------- ---------------------

Repellent hard coat layer coating liquid 1

-------------------------------------------------- ---------------------

· Smectite (Lucentite STN, manufactured by COP Chemical) 1.00 mass%

Resin particles (TECH POLYMER SSX, manufactured by Sekisui Chemical Co., Ltd.) 8.00 mass%

· Acrylate monomer (NK ester A9550, manufactured by Shin Nakamura Kagaku Kogyo Co., Ltd.) 87.79 mass%

Polymerization initiator (Irgacure 907, BASF) 3.00 mass%

· Leveling agent (P-4) 0.15 mass%

Dispersant (DISPERBYK-2164, manufactured by Big Chem Japan) 0.06 mass%

-------------------------------------------------- ---------------------

[Chemical formula 10]

(Preparation of Resin Particle Dispersion)

The light-transmitting resin particle dispersion was prepared by gradually adding light-transmitting resin particles (Tech polymer SSX, manufactured by Sekisui Chemical Co., Ltd.) to the stirred MIBK solution until the solid concentration of the dispersion became 30% by mass and stirring for 30 minutes did.

(Preparation of smectite dispersion liquid)

The smectite dispersion was prepared by gradually adding smectite (Lucentite STN, manufactured by COPPER CHEMICAL CO., LTD.) To MEK and gradually stirring for 30 minutes by using all the MEK used in the non-light-fast hard coat layer coating liquid 1.

(Draining (coating) of antiglare layer 1)

The support on which the optically anisotropic layer was formed was wound in the form of a roll and an antiglare layer was formed so as to have a film thickness of 4 탆 by using the repellent hard coat layer coating liquid 1.

Specifically, each coating liquid was coated on the conditions of a conveying speed of 30 m / min by a die coating method using a slot die described in Example 1 of JP-A-2006-122889, dried at 80 DEG C for 150 seconds, Cm &lt; ² &gt; and an irradiation dose of 180 mJ / cm &lt; ² &gt; using an air-cooled metal halide lamp (manufactured by I Graphics Co., Ltd.) having a nitrogen peroxide concentration of about 0.1% A hard coat layer was formed.

[Example 13]

An optical film was produced in the same manner as in Example 1 except that the formation of the optically anisotropic layer was changed to that shown below.

(Formation of optically anisotropic layer A)

The surface of the alignment film was continuously rubbed in the direction of 60 degrees to the left with respect to the longitudinal direction of the transparent support. On the rubbing treatment side, the following optically anisotropic layer coating liquid was applied using a bar coater. Next, the film surface was at a temperature of 115 ℃ heat aging for 90 seconds, irradiation amount of ultraviolet rays was cooled to 80 ℃ using the air cooling metal halide lamp of 20mW / cm ² (Eye Graphics Co., Ltd. No.) in the air 200mJ / cm ² the And the optically anisotropic layer A was formed by fixing the orientation state. The optically anisotropic layer A formed was perpendicular to the slow axis direction with respect to the rubbing direction and the discotic liquid crystal was vertically aligned. The retardation values at the wavelengths of 450 nm, 550 nm and 650 nm of the optically anisotropic layer A were as follows. The thickness of the optically anisotropic layer was 2.5 mu m.

ReA (450): 273 nm

ReA (550): 250 nm

ReA (650): 240 nm

ReA (450) / ReA (650): 1.14

-------------------------------------------------- ---------------------

Composition of optically anisotropic layer coating liquid (for forming optically anisotropic layer A)

-------------------------------------------------- ---------------------

· Discotic liquid crystal E-1 80 parts by mass

· Discotic liquid crystal 2 20 parts by mass

· Alignment film interface orientation first 0.55 parts by mass

· Alignment film interface orientation second 0.05 parts by mass

Fluorine compounds 0.1 parts by mass

· Modified trimethylol propane triacrylate 10 parts by mass

· Photopolymerization initiator 3.0 parts by mass

(Irgacure 907, manufactured by Chiba Specialty Chemicals Co., Ltd.)

· Interlayer alignment agent 0.6 parts by mass

· Methyl ethyl ketone 180 parts by mass

· Cyclohexanone 20 parts by mass

-------------------------------------------------- ---------------------

(11)

[Chemical Formula 12]

(Formation of optically anisotropic layer B)

The surface of the optically anisotropic layer A was rubbed continuously in the direction orthogonal to the slow axis of the optically anisotropic layer A. [ The following coating liquid for an optically anisotropic layer was applied on the rubbing treatment surface using a bar coater. Next, aged for 60 seconds by heating at a film surface temperature of 60 ℃, and by using the air cooling metal halide lamp of 20mW / cm ² (Eye Graphics Co., Ltd. No.) in the air, and irradiated with ultraviolet rays, the optically anisotropic layer by fixing the orientation state B was formed. The optically-anisotropic layer B thus formed was horizontally oriented in the rod-like direction with the slow axis direction parallel to the rubbing direction. The retardation values at the wavelengths of 450 nm, 550 nm and 650 nm of the optically anisotropic layer B were as follows. The thickness of the optically anisotropic layer B was 1.0 mu m.

ReB (450): 141 nm

ReB (550): 125 nm

ReB (650): 120 nm

ReB (450) / ReB (650): 1.18

The ReA 550 of the optically anisotropic layer A and the ReB 550 of the optically anisotropic layer B corresponded to ReA (550)> ReB (550).

-------------------------------------------------- ---------------------

Composition of optically anisotropic layer coating liquid (for forming optically anisotropic layer B)

-------------------------------------------------- ---------------------

· Rod-shaped liquid crystalline compound 1 90 parts by mass

Rod-shaped liquid crystalline compound 2 10 parts by mass

· Photopolymerization initiator 3.0 parts by mass

(Irgacure 907, manufactured by Chiba Specialty Chemicals Co., Ltd.)

· Sensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.) 1.0 part by mass

Fluorine compounds 0.5 parts by mass

· Methyl ethyl ketone 400 parts by mass

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[Chemical Formula 13]

The adhesiveness, wrinkle (deformation), irregularity of in-plane retardation, and linearity of each optical film thus produced were evaluated by the following methods. These results are shown in Table 1 below.

In the following Table 1, regarding the shape of the optically anisotropic layer, the shape of the optically anisotropic layer formed by the method of Example 1 is referred to as "A " and the shape of the optically anisotropic layer formed by the method of Example 8 Quot; B ", the form of the optically anisotropic layer formed by the method in Example 9 is abbreviated as "C ", and the form of the optically anisotropic layer formed by the method in Example 13 is abbreviated as" D ".

Similarly, in the following Table 1, regarding the liquid crystal material of the optically anisotropic layer, the case of using a discotic liquid crystal compound is abbreviated as "DLC: Discotic Liquid Crystal ".

&Lt; Adhesion >

The adhesion was evaluated by the cross-cut method described in JIS K5600-5-6: 1999.

Specifically, 100 pieces of checkerboard eyes were drawn at intervals of 1 mm on the surface (optically anisotropic layer side) of the produced optical film, and NT tape of Nitto Denko Co., Ltd. was pasted, followed by 10 reciprocating strokes of 100 g in weight, Was repeated five times, and the number of remaining portions in the 100 cells without peeling was counted and evaluated according to the following criteria.

A: The number of peelings is 10 or less and excellent adhesion

B: 11 to 99 peeled off, poor adhesion

C: 100 pieces are peeled off, and the adhesion is very poor

<Presence of wrinkles>

The presence or absence of wrinkles was evaluated by visually observing the unevenness in the longitudinal direction when the produced optical film was cut in a length of 1 m and spread in a state in which no tension was applied.

A: Significant unevenness is not recognized.

B: There is one remarkable irregularity in the plane.

C: There are more than two uneven irregularities in the plane.

<Non-uniformity of in-plane retardation>

The irregularity of in-plane retardation was measured by measuring Re using KOBRA-21ADH (manufactured by Oji Keisoku Kiki Co., Ltd.) for arbitrary 100 of the produced optical films, and the difference between the maximum value and the minimum value of each maximum value Respectively.

A: The difference between the maximum Re and the minimum Re is 5 nm or less

B: difference between maximum Re and minimum Re is more than 5 nm and less than 8 nm

C: difference between maximum Re and minimum Re is more than 8 nm, less than 10 nm

&Lt; 3D display unevenness &

With respect to the optical film whose shape of the optically anisotropic layer is A, 3D display irregularity was evaluated by the following method.

For the 3D display irregularity, the forced evaluation was performed on an image which is easy to recognize the 3D display irregularity.

Specifically, a stripe image in which white and black colors are alternately arranged in the vertical direction is displayed on the liquid crystal display device, and the glasses on the side where the white stripe is visible on the front face are shielded by attaching the 3D glasses to observe the liquid crystal display And evaluated according to the following criteria. In this evaluation, the black display portion in the display surface means no or little crosstalk, and the portion in which the luminance leakage is visible and the white display portion means that there is crosstalk.

(Evaluation standard)

A: In the compulsory evaluation, the whole of the display surface is black, the crosstalk is not visually observed at all, or a slight luminance leak is visually recognized but the crosstalk is not visually recognized even in the evaluation by the 3D video source.

B: Brightness leakage is observed in the forced evaluation, but almost no crosstalk is visually observed in the evaluation by the 3D video source.

C: The luminance leak is also recognized in the forced evaluation, and the crosstalk is also recognized in the evaluation by the 3D video source.

<Linearity>

With regard to the optical film whose shape of the optically anisotropic layer is A, the linearity was evaluated by the following method.

The pattern of the optical film The stripe pattern of the optically anisotropic layer evaluated the maximum amount shaken from the stripe line.

Specifically, the optical film was cut into a size that can be conjugated to a 42-inch wide liquid crystal with the long side in the longitudinal direction, and the maximum amount in which the stripe swung from the straight line was obtained. Practically, A, B and C are preferable, A and B are more preferable, and A is most preferable.

A: The maximum amount of shaking is within 10μm

B: The maximum amount of shaking is within 10μm to 20μm

C: The maximum amount of shaking is within 20μm to 30μm

D: Maximum amount of shaking within 30μm to 60μm

E: The maximum amount of shaking exceeds 60μm

&Lt; Pattern characteristics (boundary line width) >

For the optical film having the shape of the optically anisotropic layer A, the pattern characteristics were evaluated by the following method.

The patterned optically anisotropic layer of the optical film was laminated so that the slow axis of either the first retardation region or the second retardation region was parallel to the polarization axis of either one of the two polarizing plates combined at the orthogonal positions And a polarizing plate having a retardation of 530 nm was placed on the optically anisotropic layer such that its slow axis was at an angle of 45 ° with the polarizing axis of the polarizing plate. The width of the stripe pattern boundary region observed at this time is defined as the border width. The smaller the boundary line width is, the higher the uniformity in the plane is, and the better 3D image quality can be obtained.

[Table 1]

As shown in Table 1, when the average SP value of the solvent contained in the coating liquid forming the alignment film is more than 55, the thickness of the mixed layer between the transparent support and the alignment film becomes less than 50 nm, The adhesion of the interface was weakened and the alignment film peeled off (Comparative Examples 1 to 3).

When the average SP value of the solvent contained in the coating liquid forming the alignment film is less than 25, the thickness of the mixed layer between the transparent support and the alignment film becomes thicker than 200 nm, and when the coating liquid is dried, the support shrinks, (Comparative Examples 4 to 5).

Examples in which the shape of the optically anisotropic layer was changed from B to D to those in which the average SP value of the solvent contained in the coating liquid forming the alignment film was out of the range of 25 to 55 were also compared with those of Comparative Examples 1 to 5 The same tendency was found.

Even when the average SP value of the solvent contained in the coating liquid for forming the alignment film is less than 25, when a TAC film or a PET film is used as the transparent support, wrinkles are not generated but the linearity is poor, (Reference Examples 1 and 2).

On the contrary, an optical film in which an alignment film was formed using a coating liquid containing a solvent having an average SP value of 25 to 55, and a mixed layer having a thickness of 50 nm to 200 nm was formed between the transparent support and the alignment film had no wrinkles, And the adhesion of the alignment film were excellent (Examples 1 to 13).

In particular, from the comparison of Examples 1 to 7, it was found that when the average SP value of the solvent of the alignment film coating liquid was 25 to 40, the adhesion between the support and the alignment film became better.

From the comparison between Example 5 and Example 11, it was found that the pattern characteristic was improved by including the polyvinyl alcohol derivative in the alignment film.

10 Optical film
12 optically anisotropic layer
12a First phase difference region
a a phase axis of the first retardation region
12b &lt; / RTI &gt;
b The ground axes of the second phase difference region
14 Alignment layer
15 mixed layer
16 transparent support
18 hard coat layer
20 polarizer
22 Polarizer
23 absorption axis of polarizer
24 polarizer protective film
30 liquid crystal display
32 liquid crystal cell
34 polarizer
36, 38 Polarizer protective film
40 organic EL display device
42 Organic EL display panel

Claims (13)

As an optical film having a transparent support, an orientation film, and an optically anisotropic layer in this order,
Wherein the transparent support comprises an acrylic resin,
Wherein the transparent support has a thickness of 50 nm to 200 nm and a mixed layer in which the constituent material of the transparent support and the constituent material of the orientation film are mixed between the transparent support and the orientation film. The method according to claim 1,
Plane retardation at a wavelength of 550 nm of the optically-anisotropic layer is 40 nm to 240 nm. The method according to claim 1 or 2,
Wherein the alignment film comprises a polyvinyl alcohol derivative. The method according to any one of claims 1 to 3,
Wherein the optically anisotropic layer is a patterned optically anisotropic layer having at least two retardation regions different from each other in at least one of an in-plane slow axis direction and an in-plane retardation. The method according to any one of claims 1 to 4,
Further, an optical film having a hard coat layer. An optical film according to any one of claims 1 to 5, and a polarizer having a polarizer. An image display apparatus comprising an optical film according to any one of claims 1 to 5, a polarizer, and a liquid crystal cell or an organic EL display panel. The method of claim 7,
And the optical film, the polarizer, and the liquid crystal cell from the viewer side in this order. The method of claim 7,
And the polarizer, the optical film, and the liquid crystal cell from the viewer side in this order. The method of claim 7,
And the polarizer, the optical film, and the organic EL display panel from the viewer side in this order. A method for producing an optical film according to any one of claims 1 to 5,
An orientation film is formed on a transparent support including an acrylic resin by using a coating solution containing one or more solvents and having an average SP value of the solvent of 25 to 55, A mixed layer / orientation film forming step of forming a mixed layer having a thickness of 50 nm to 200 nm between the orientation film and a constituent material of the transparent support and a constituent material of the orientation film being mixed,
An optically anisotropic layer forming step of forming an optically anisotropic layer on the alignment film by using a composition for forming an optically anisotropic layer containing a liquid crystal compound to produce an optical film. The method of claim 11,
And the average SP value of the solvent is 25 to 40. The optical film according to claim 1, The method according to claim 11 or 12,
Wherein the solid content concentration of the coating liquid is 60 mass% or less.

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